Portable endoscope system

ABSTRACT

A portable endoscope system having an illuminating light guide for transmitting light for illuminating an object, and an illuminating light supply unit for supplying illuminating light to the illuminating light guide. The entrance end portion of the illuminating light guide is disposed in an endoscope control part. The portable endoscope system includes a device for detachably connecting the illuminating light supply unit and the control part, and a connecting device for sealing a joint between the illuminating light supply unit and the control part. The connecting device seals the joint in a watertight manner so that water will not enter the portable endoscope system when the illuminating light supply unit is attached to the control part.

This application is a continuation of application Ser. No. 08/496,961, filed Jun. 30, 1995, now abandoned.

BACKGROUND OF THE INVENTION

The present invention relates to subject matter contained in Japanese Patent Application Nos. 6-151890 (filed on Jul. 4, 1994), 6-155535 (filed on Jul. 7, 1994), 7-94623 (filed on Apr. 20, 1995), 7-94624 (filed on Apr. 20, 1995) and 7-94625 (filed on Apr. 20, 1995), which are expressly incorporated herein by reference in their entireties.

1. Field of the Invention

The present invention relates to a portable endoscope system in which a unit for supplying illuminating light to an illuminating light guide is detachably attached to an endoscope control part.

2. Description of the Prior Art

A conventional portable endoscope system has a light-emitting device for illumination which is provided in an endoscope control part. In general, an illuminating light supply unit which contains a miniature bulb and a dry battery is attached to the control part.

Accordingly, when the endoscope system is dipped in a disinfectant, it is likely that the disinfectant will enter the inside of the endoscope, causing electrical and mechanical failures. For this reason, it is not easy to sufficiently wash and disinfect the endoscope after use. However, if washing and disinfection of the endoscope are insufficient, there is a fear that bacteria and viruses may be transmitted from one patient to another through the contaminated endoscope.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a portable endoscope system which can be sufficiently washed and disinfected without a fear of a disinfectant entering the inside of the endoscope even when it is dipped in the disinfectant.

Other objects and advantages of the present invention will become apparent from the following detailed description of illustrated embodiments of the invention.

According to the present invention, there is provided a portable endoscope system having an illuminating light guide for transmitting light for illuminating an object, and an illuminating light supply unit for supplying illuminating light to the illuminating light guide. The entrance end portion of the illuminating light guide is disposed in an endoscope control part. The portable endoscope system includes a device for detachably connecting together the illuminating light supply unit and the control part, and a device for sealing a joint between the illuminating light supply unit and the control part, which is made by the connecting device, in a watertight manner so that no water will externally enter the portable endoscope system in a state where the illuminating light supply unit is attached to the control part.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be more fully understood from the description of preferred embodiments of the invention set forth below, together with the accompanying drawings, in which:

FIG. 1 is a side view showing a first embodiment of the portable endoscope system according to the present invention with an illuminating light supply unit attached to a control part thereof;

FIG. 2 is a sectional plan view showing the first embodiment of the present invention with the illuminating light supply unit detached from the control part;

FIG. 3 is a sectional plan view showing the first embodiment of the present invention with the illuminating light supply unit attached to the control part;

FIG. 4 is a sectional plan view showing a second embodiment of the portable endoscope system according to the present invention with an illuminating light supply unit detached from a control part thereof;

FIG. 5 is a sectional plan view showing the second embodiment of the present invention with the illuminating light supply unit attached to the control part;

FIG. 6 is a side view of a third embodiment of the portable endoscope system according to the present invention;

FIG. 7 is a rear view of the third embodiment of the present invention;

FIG. 8 is a rear view showing the third embodiment of the present invention with an AC/DC adapter connected thereto;

FIG. 9 is a fragmentary sectional view of the third embodiment of the present invention, showing a joint between an endoscope control part and an illuminating light supply unit;

FIG. 10 is a fragmentary sectional view of the third embodiment of the present invention, showing the joint in a state where the illuminating light supply unit is detached from the endoscope control part;

FIG. 11 is a fragmentary sectional view taken along the lines XI--XI, (see FIG. 12), showing a battery chamber and a cap, which constitute a part of the illuminating light supply unit in the third embodiment of the present invention;

FIG. 12 is a sectional view of the second embodiment taken at a level shown by line XII--XII in FIG. 11;

FIG. 13 is a fragmentary sectional view taken along the lines XIII--XIII, (see FIG. 14), showing the cap of the illuminating light supply unit in a switch-off state in the third embodiment of the present invention;

FIG. 14 is a sectional view of the second embodiment taken at a level shown by line XIV--XIV in FIG. 13; and

FIGS. 15 to 17 are fragmentary sectional views respectively showing caps of illuminating light supply units in fourth through sixth embodiments of the present invention.

DESCRIPTION OF THE EMBODIMENTS

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a control part and neighboring constituent elements of a portable endoscope system according to a first embodiment of the present invention. The portable endoscope system has an insert part 1 which is armored with a flexible tube, and a control part 2 which is connected to the proximal end of the insert part 1.

About three fourths from the bottom of the control part 2 is grip portion 2a. A forceps inlet 4 is provided between the grip portion 2a and the insert part 1, so as to project obliquely forward.

The control part 2 has a control mechanism portion 5 above the grip portion 2a. The control mechanism portion 5 has a suction control valve 6 which is disposed on the front side thereof to carry out a suction operation through a forceps channel (not shown) inserted in the insert part 1. The control mechanism portion 5 further has a bending control lever 7 which is disposed on the rear side thereof to effect bending control of a remote-controlled bendable portion (not shown) which is formed at the distal end of the insert part 1. In addition, an eyepiece 8 is provided on the top of the control mechanism portion 5.

A light guide fiber bundle 9 for transmitting light for illuminating an object has an entrance end portion thereof disposed in the control mechanism portion 5, and extends through the insert part 1 and the grip portion 2a of the control part 2. The exit end portion of the light guide fiber bundle 9 is disposed in the distal end of the insert part 1.

An illuminating light supply unit 30 for supplying illuminating light to the light guide fiber bundle 9 is detachably attached to a side of the control mechanism portion 5.

FIG. 2 is an enlarged sectional view showing the portable endoscope system in a state where the illuminating light supply unit 30 is detached from the control part 2.

The control mechanism portion 5 of the control part 2 is armored with a casing 11 made of a plastic material. A lever bearing cylinder 12 that supports the bending control lever 7 is fitted in a through-hole provided in the casing 11, and sealed in a watertight manner. Similarly, the suction control valve 6 is fitted in a through-hole provided in the casing 11, and sealed in a watertight manner. The respective proximal end portions of the lever bearing cylinder 12 and the suction control valve 6 are secured to a frame 13 in the control part 2.

A cover 15 is fitted in a relatively large opening provided in a side of the casing 11, and a sealing 0-ring 16 is attached to the fitting surface of the cover 15 to prevent water from entering the inside of the control part 2 through the gap between the cover 15 and the peripheral wall of the opening. It should be noted that, although the O-ring 16 is compressed when it is disposed in the area of fit between the cover 15 and the casing 11, the cross-section of the O-ring 16 in a natural state before it is compressed is shown in the figure (the same shall apply hereinafter).

A support cylinder 17 is disposed on the central axis of a bore formed in the center of the cover 15. The proximal end portion of the support cylinder 17 is secured to the frame 13 in the control part 2. A light guide mounting cylinder 18 is screwed to the support cylinder 17. The distal end portion of the light guide mounting cylinder 18 projects outwardly from the support cylinder 17. The entrance end portion of the light guide fiber bundle 9 is secured with a screw at the central axis position in the light guide mounting cylinder 18.

A lens mounting cylinder 19 is fitted on the projecting end portion of the light guide mounting cylinder 18 in a cap-like fashion, and firmly thread-engaged with it. The lens mounting cylinder 19 has a convex meniscus lens 20 which is bonded to the distal end portion thereof in a watertight manner. Thus, the convex meniscus lens 20 is set at a position close to the entrance end surface of the light guide fiber bundle 9 so as to face it.

An O-ring retaining frame 22 is disposed to surround the joint between the support cylinder 17 and the light guide mounting cylinder 18. The O-ring retaining frame 22 is fitted at the outer surface thereof to the wall of the bore provided in the center of the cover 15, and fitted at the inner surface thereof to the outer surface of the lens mounting cylinder 19. O-rings 24 and 25 are attached to the outer and inner surfaces, respectively, of the O-ring retaining frame 22 to prevent water from entering the inside of the control part 2 through the gap between the O-ring retaining frame 22 and the cover 15 or through the gap between the O-ring retaining frame 22 and the lens mounting cylinder 19.

Thus, the control part 2 is formed into a watertight structure which prevents water from externally entering the control part 2 through any portion thereof. The insert part 1 is similarly formed into a watertight structure, as a matter of course. Accordingly, even when the portable endoscope system is dipped in a disinfectant or other liquid with no illuminating light supply unit 30 attached thereto, there is no fear of the disinfectant or other liquid entering the inside of the endoscope.

A connecting cylinder 23 is disposed to surround an area which extends from the Lens mounting cylinder 19 to the O-ring retaining frame 22. The proximal end portion of the connecting cylinder 23 is screwed to the inner surface of the bore in the cover 15. The outer peripheral surface of an intermediate portion of the connecting cylinder 23 is provided with an external thread 23a. The outer peripheral surface of the distal end portion of the connecting cylinder 23, which lies forward of the external thread 23a, is a tapered surface which becomes gradually smaller in diameter toward the distal end. A sealing O-ring 26 is attached to the tapered surface at an intermediate position between the external thread 23a and the distal end.

The illuminating light supply unit 30 has an L-shaped cylindrical configuration as a whole. The illuminating light supply unit 30 has a casing 31 made of a plastic material. A light source lamp 32 is disposed in the bend of the L-shaped casing 31. The light source lamp 32 is attached to a lamp socket 33.

The light source lamp 32 is disposed on the axis of the short cylindrical portion of the L-shaped casing 31. A reflecting mirror 34 is attached to the lamp socket 33 so as to surround the light source lamp 32 in order to converge illuminating light from the light source lamp 32 on the axis of the short cylindrical portion of the L-shaped casing 31.

The casing 31 is formed with an opening behind the lamp socket 33. A bottom cover 35 is detachably thread-engaged with the mouth of the opening. A sealing O-ring 36 is disposed between the fitting surfaces of the bottom cover 35 and the casing 31 to prevent water from entering the inside of the illuminating light supply unit 30 through the gap between the bottom cover 35 and the casing 31. In addition, a compression coil spring 37 is interposed between the bottom cover 35 and the lamp socket 33 to secure the lamp socket 33 and the reflecting mirror 34 by resilient force from the spring 37.

A battery 38 is accommodated in the long cylindrical portion of the L-shaped casing 31. The battery 38 may be either a dry battery or a rechargeable nickel-cadmium battery.

A battery casing cover 39 made of a plastic material is detachably thread-engaged with an opening provided at an outer end of the battery accommodating portion of the casing 31. A sealing O-ring 40 is disposed in the boundary between the battery casing cover 39 and the peripheral wall of the opening to prevent water from entering the inside of the illuminating light supply unit 30 through the gap therebetween. The battery 38 can be replaced by detaching the battery casing cover 39 from the casing 31.

Negative electrodes 41 and 42 are disposed in the battery casing cover 39 and the casing 31, respectively. A positive electrode 43 is disposed in the casing 31. The electrodes 42 and 43 are connected to the light source lamp 32 through respective lead wires 43'.

It should be noted that a switch (not shown) for ON/OFF controlling the light source lamp 32 is provided in an intermediate portion of the wiring for supplying electric power to the light source lamp 32. The switch is also sealed in a watertight manner so that no water can externally enter the inside of the illuminating light supply unit 30.

A connecting cylinder receiving cylinder 46 is secured in an opening provided at the end of the short cylindrical portion of the L-shaped casing 31 by fastening a nut 47 from the inner side of the casing 31. The connecting cylinder receiving cylinder 46 has a tapered opening which is so shaped as to engage with the tapered surface of the connecting cylinder 23, which is provided on the control part 2.

A sealing O-ring 48 is disposed between the fitting surfaces of the connecting cylinder receiving cylinder 46 and the casing 31 to prevent water from entering the inside of the illuminating light supply unit 30 through the gap therebetween. A plane-parallel transparent plate 49 is bonded to the inner end portion of the connecting cylinder receiving cylinder 46 in a watertight manner.

Thus, the illuminating light supply unit 30 is formed into a watertight structure which prevents water from externally entering the illuminating light supply unit 30 through any portion thereof. Accordingly, even when the illuminating light supply unit 30 alone, which is not attached to the control part 2, is dipped in a disinfectant or other liquid, there is no fear of the disinfectant or other liquid entering the inside of the illuminating light supply unit 30.

Further, a fastening ring 50 is attached to the outer peripheral portion of the connecting cylinder receiving cylinder 46 so as not to come off axially. The fastening ring 50 has an internal thread 50a for engagement with the external thread 23a of the connecting cylinder 23.

Accordingly, when the illuminating light supply unit 30 which is in the state shown in FIG. 2 is to be connected to the control part 2, it is brought close to the control part 2, and the tapered surfaces of the connecting cylinder 23 and the connecting cylinder receiving cylinder 46 are brought into close contact with each other. Then, the internal thread 50a of the fastening ring 50 is engaged with the external thread 23a of the connecting cylinder 23. Thus, the illuminating light supply unit 30 is connected to the control part 2, as shown in FIG. 3.

At this time, the O-ring 26, which is attached to the tapered surface of the connecting cylinder 23, is compressed by the connecting cylinder receiving cylinder 46 so as to prevent water from externally entering the joint between the illuminating light supply unit 30 and the control part 2. Accordingly, even when the portable endoscope system is dipped in a disinfectant or other liquid with the illuminating light supply unit 30 attached to the control part 2, there is no fear of the disinfectant or other liquid entering the inside of the endoscope.

In the portable endoscope system having the illuminating light supply unit 30 attached to the control part 2 as described above, illuminating light that is emitted from the light source lamp 32 is reflected by the reflecting mirror 34, and then passes through the transparent plate 49 and the lens 20. Thus, the illuminating light converges on the entrance end surface of the light guide fiber bundle 9, and enters the light guide fiber bundle 9.

Since the connecting cylinder 23 and the connecting cylinder receiving cylinder 46 are brought in close contact with each other at the respective tapered surfaces, the illuminating light supply unit 30 can be immovably secured to the control part 2 by tightly fastening the fastening ring 50 to the connecting cylinder 23.

However, the illuminating light supply unit 30 is allowed to rotate freely about the optical axis of the illuminating light by slightly untightening the fastening ring 50. Accordingly, the illuminating light supply unit 30 can be set in the most convenient position for the user by appropriately adjusting the angle of the illuminating light supply unit 30 relative to the control part 2, which is shown by reference symbol A in FIG. 1, and tightly fastening the fastening ring 50 with the illuminating light supply unit 30 maintained in the desired position.

Thus, the portable endoscope system according to the first embodiment of the present invention is formed in a watertight structure which prevents water from externally entering the inside thereof in a state where the illuminating light supply unit is attached to the endoscope control part. Accordingly, the endoscope system can be dipped in a disinfectant or other liquid with the illuminating light supply unit attached to the endoscope without a fear of the disinfectant or other liquid entering the inside of the endoscope. Therefore, the endoscope can be completely washed and disinfected.

If the illuminating light supply unit and the endoscope control part are each formed as a watertight unit, these units can be individually dipped in a disinfectant or other liquid, and sufficiently washed and disinfected without a fear of the disinfectant or other liquid entering the insides thereof.

Further, since the illuminating light supply unit can be set in the most convenient position for the user by making it possible to adjust the angle of the illuminating light supply unit relative to the control part, the controllability of the endoscope improves.

FIGS. 4 and 5 show a second embodiment of the present invention, in which the O-ring 25 which is fitted between the O-ring retaining frame 22 and the lens mounting cylinder 19 in the first embodiment is removed, and in which an air passage 28 which provides communication between the inside and outside of the control part 2 is formed between the inner peripheral surface of the connecting cylinder 23 and the outer peripheral surface of the lens mounting cylinder 19. The rest of the arrangement is the same as that of the first embodiment. Thus, the control part 2 is formed into a watertight structure which prevents water from externally entering the control part 2 through any portion thereof, except for the air passage 28.

Accordingly, in a state where the illuminating light supply unit 30 is not attached to the control part 2, as shown in FIG. 4, the inside and outside of the endoscope are communicated with each other through the air passage 28. Therefore, even when the endoscope is put in an ethylene oxide gas sterilizer, or the like, and placed under vacuum environmental conditions, no accident will occur. More specifically, there is no likelihood that a flexible portion of the endoscope will rupture. Further, since the illuminating light supply unit 30 has no flexible portion in the outer wall thereof, no rupture will occur even if it is put in an ethylene oxide sterilizer or the like.

In a state where the illuminating light supply unit 30 is connected to the control part 2, as shown in FIG. 5, the air passage 28 opens inside the joint sealed with the O-ring 26. Therefore, even when the endoscope system is dipped in a disinfectant or other liquid with the illuminating light supply unit 30 attached to the control part 2, no disinfectant will enter the inside of the endoscope system.

Thus, according to the second embodiment of the present invention, an air passage for providing communication between the inside and outside of the control part is formed in the control part. Therefore, when the illuminating light supply unit is detached from the endoscope, the inside and outside of the endoscope communicate with each other, and thus the endoscope can be sterilized with ethylene oxide gas without causing a rupture, without a need of any special structure for this purpose.

Since the air passage is formed inside the watertight connecting mechanism for connecting the illuminating light supply unit to the control part, when the illuminating light supply unit is connected to the control part, the air passage is shut off from the outside by the connecting mechanism. Therefore, even when the endoscope system is dipped in a disinfectant, there is no possibility of the disinfectant entering the endoscope system through the air passage.

Further, the control part is formed into a watertight structure which prevents water from externally entering the inside of the control part through any portion thereof, except for the air passage. The illuminating light supply unit is also formed into a watertight structure, thereby enabling the control part and the illuminating light supply unit to be completely disinfected and sterilized.

FIGS. 6 and 7 arc side and rear views, respectively, which show a control part and neighboring constituent elements of a portable endoscope system according to a third embodiment of the present invention. The portable endoscope system has an insert part 101 which is armored with a flexible tube. The proximal end of the insert part 101 is connected to the lower end portion of a control part 102.

About three fourths from the bottom of the control part 102 is grip portion 102a. A forceps inlet 104 is provided between the grip portion 102a and the insert part 101 so as to project obliquely forward. A pressure control valve 103 is used to control the pressure in the endoscope, which is formed into an airtight structure.

The control part 102 has a control mechanism portion 105 above the grip portion 102a. The control mechanism portion 105 has a suction control valve 106 which is disposed on the front side thereof to carry out a suction operation through a forceps channel (not shown) inserted in the insert part 101. The control mechanism portion 105 further has a bending control lever 107 which is disposed on the rear side thereof to effect bending control of a remote-controlled bendable portion (not shown) which is formed at the distal end of the insert part 101. In addition, an eyepiece 108 is provided on the top of the control mechanism portion 105.

A light guide fiber bundle 109 for transmitting light for illuminating an object has an entrance end portion thereof disposed in the control mechanism portion 105, and extends through the insert part 101 and the grip portion 102a of the control part 102. The exit end portion of the light guide fiber bundle 109 is disposed in the distal end of the insert part 101.

An illuminating light supply unit 130 for supplying illuminating light to the light guide fiber bundle 109 is detachably attached to a side of the control mechanism portion 105 in such a manner as to project in a straight line perpendicularly to the axis of the control mechanism portion 105.

As shown in FIG. 7, the illuminating light supply unit 130 contains a light source lamp 132 for emitting illuminating Light which is to be supplied to the light guide fiber bundle 109, and a battery 100 as a power supply for lighting the light source lamp 132. The battery 100 may be any type of battery, e.g., a dry battery or a rechargeable nickel-cadmium battery.

The battery 100 can be replaced by removing a cap 150 which is detachably attached to the outer end of the illuminating light supply unit 130. As shown in FIG. 8, an AC/DC adapter 180 may be connected to the illuminating light supply unit 130 in place of the battery 100.

The AC/DC adapter 180 has a plug 182 which can be inserted into an outlet for a commercial AC power supply of 100 V or 200 V, for example, which is supplied for general domestic use. Thus, the commercial AC voltage can be converted into a DC voltage of 3 V, for example, to light the light source lamp 132.

FIG. 9 shows the joint between the control part 102 and the illuminating light supply unit 130 and its vicinities. The control mechanism portion 105 of the control part 102 is armored with a casing 111 made of an electrically insulating plastic material.

A lever bearing cylinder 112 that supports the bending control lever 107 is fitted in a bore provided in the casing 111, and sealed in a watertight manner. Similarly, the suction control valve 106 is fitted in a bore provided in the casing 111, and sealed in a watertight manner. The respective proximal end portions of the lever bearing cylinder 112 and the suction control valve 106 are secured to a frame 113 in the control part 102. The frame 113 is made of a material having mechanical strength and electrical conductivity, such as a metallic material or a carbon resin material (hereinafter referred to as "metal frame 113").

A cover 115 which is made of an electrically insulating plastic material is fitted in a relatively large opening provided in a side of the casing 111, and a sealing O-ring 116 is attached to the fitting surface of the cover 115 to prevent water from entering the inside of the control part 102 through the gap between the cover 115 and the peripheral wall of the opening. In addition, a detent 121 is formed in the area between the cover 115 and the casing 111 to prevent the cover 115 and the casing 111 from rotating relative to each other.

A support cylinder 117 is disposed on the central axis of a through-hole formed in the center of the cover 115. The proximal end portion of the support cylinder 117 is secured to the metal frame 113 in the control part 102. A light guide mounting cylinder 118 is screwed to the support cylinder 117. The distal end portion of the light guide mounting cylinder 118 projects outwardly from the projecting end of the support cylinder 117.

The entrance end portion of the light guide fiber bundle 109 is secured with a screw at the central axis position in the light guide mounting cylinder 118. A convex meniscus lens 120 is bonded to the projecting end portion of the light guide mounting cylinder 118 in a watertight manner so as to face the entrance end surface of the light guide fiber bundle 109.

A cylindrical unit receiving socket 127 is fitted in a through-hole which is formed in the cover 115 such that the socket 127 projects outwardly to receive (connect) the illuminating light supply unit 130, which is detachably attached to the control part 102. The unit receiving socket 127 is made of a stainless steel, for example, and secured by being pressed inwardly with a metallic fastening ring 128 which is thread-engaged with the support cylinder 117.

It should be noted that an insulating cylinder 129, which is made of an electrically insulating plastic material, is interposed between the unit receiving socket 127 and the fastening ring 128 to prevent these members from coming in contact with each other. Thus, the unit receiving socket 127 and the fastening ring 128 are electrically insulated from each other.

Thus, the cover 115 and the insulating cylinder 129, which are in contact with the unit receiving socket 127 provided on the control part 102, are both electrically insulating members. Therefore, even if an external leakage current flows to the unit receiving socket 127, which projects outwardly from the control part 102, the leakage current will not be conducted to the other members of the control part 102.

It should be noted that a sealing O-ring is disposed in the area of fit between each pair of mating members disposed inside the bore of the cover 115, thereby forming the control part 102 into a watertight structure which prevents water from externally entering the control part 102 through any portion thereof. The insert part 101 is similarly formed into a watertight structure, as a matter of course.

The illuminating light supply unit 130 has a straight cylindrical configuration as a whole. The illuminating light supply unit 130 is divided into a lamp chamber portion 130a, which is closer to the joint to the control part 102, and a battery chamber portion 130b, which is away from the joint to the control part 102. FIG. 9 shows the whole lamp chamber portion 130a.

The outer wall of the battery chamber portion 130b is formed from a cylindrical outer casing 131b which is made of a material of good corrosion resistance (chemical resistance), for example, a stainless steel, a metallic material which has been subjected to chemical-resistant surface treatment, or a plastic material. Further, a cylindrical inner casing 131a is disposed inside the outer casing 131b in contact with the inner peripheral surface of the outer casing 131b. The inner casing 131a is made of a material of good electrical conductivity, for example, copper, or a copper alloy such as phosphor bronze.

A lamp socket 133 is secured to the inner casing 131a through some parts at the boundary between the lamp chamber portion 130a and the battery chamber portion 130b. The light source lamp 132 is detachably inserted into the lamp socket 133. The lamp socket securing structure will be described later.

A cylindrical lamp chamber casing 135a constitutes the outer wall of the lamp chamber portion 130a. The lamp chamber casing 135a is formed of a material of mechanical strength, for example, stainless steel, and connected to the outer casing 131b.

Relative rotation between the lamp chamber casing 135a and the outer casing 131b is prevented by engagement of a rotation preventing pin 137, which projects from the lamp chamber casing 135a, with a groove 136 formed in the outer casing 131b.

A securing ring 138 is secured to the lamp chamber casing 135a by the rotation preventing pin 137 and held between the outer casing 131b and a retaining ring 135b which is fitted on the outer periphery of the lamp chamber casing 135a, and which is thread-engaged with the outer casing 131b. Thus, the lamp chamber casing 135a and the outer casing 131b are fixed in the axial direction. An O-ring 139 seals the area of joint between the lamp chamber casing 135a and the outer casing 131b.

A reflecting mirror 134 is bonded to the distal end portion of the lamp chamber casing 135a so as to surround the light source lamp 132 in order to converge illuminating light from the light source lamp 132 toward the entrance end surface of the light guide fiber bundle 109.

A transparent cover glass 149 is secured to the front end surface of the reflecting mirror 134 by a retaining nut 140. The outer peripheral surface of the cover glass 149 is coated with a sealing compound to prevent water from externally entering the lamp chamber casing 135a.

An O-ring 141 (annular sealing member) is fitted on the outer peripheral surface of the distal end portion of the lamp chamber casing 135a so as to come in close contact with the inner peripheral surface of the unit receiving socket 127 in order to seal the joint (i.e., the area between the inner peripheral surface of the unit receiving socket 127 and the outer peripheral surface of the lamp chamber casing 135a).

An external thread 135s is formed on the outer peripheral surface of the distal end portion of the lamp chamber casing 135a at a position which is forward of the O-ring 141. The external thread 135s is adapted to engage with an internal thread 127s which is formed on the inner peripheral surface of the unit receiving socket 127. Thus, by engaging the two threads 127s and 135s with each other, the illuminating light supply unit 130 is connected to the control part 102.

Consequently, illuminating light that is emitted from the light source lamp 132 is reflected by the reflecting mirror 134, and then passes through the cover glass 149 and the convex meniscus lens 120. Thus, the illuminating light converges on the entrance end surface of the light guide fiber bundle 109, and enters the light guide fiber bundle 109.

Thus, in a state where the illuminating light supply unit 130 is connected to the control part 102, the area of fit between the lamp chamber casing 135a and the unit receiving socket 127 is sealed by the O-ring 141.

As shown in FIG. 10, by disengaging the external thread 135s of the lamp chamber casing 135a from the internal thread 127s of the unit receiving socket 127, the illuminating light supply unit 130 is detached from the control part 102.

Since in this embodiment the external thread 135s is formed on the distal end portion of the lamp chamber casing 135a at a position forward of the position at which the O-ring 141 is fitted, the O-ring 141 does not contact the internal thread 127s of the unit receiving socket 127 when the illuminating light supply unit 130 is attached to or detached from the control part 102. Accordingly, there is no possibility of the O-ring 141 being damaged when the illuminating light supply unit 130 is attached to or detached from the control part 102.

Referring to FIG. 9, two electrodes which project rearwardly from the light source lamp 132 are inserted into the socket 133 and electrically connected to connecting pins 142a and 142b which are disposed behind the socket 133. The proximal ends of the connecting pins 142a and 142b are secured to respective electrode plates 143a and 143b which are disposed to face each other across an insulating plate 144.

One electrode plate 143a is always in contact with the positive electrode of the battery 100, and the other electrode plate 143b is electrically connected with the inner casing 131a through a retaining cylinder 146 which is made of a metal of good electrical conductivity.

These members are surrounded by an electrically insulating cylinder 145, and secured, together with the socket 133, by being pressed with a retaining nut 147 which is thread-engaged with the inner casing 131a.

FIG. 11 shows the battery chamber portion 130b. A cap 150 is detachably thread-engaged with the end portion of the cylindrical inner casing 131a, which accommodates the battery 100. The cap 150 incorporates a switch for ON/OFF controlling the supply of electric power from the battery 100 to the light source lamp 132.

An outer cylinder 151b, which is made of a material of good corrosion resistance, forms the outer wall of the cap 150. An inner cylinder 151a, which is made of a metal of good electrical conductivity, is disposed inside the outer cylinder 151b in contact with the inner peripheral surface of the outer cylinder 151b. The inner cylinder 151a is detachably thread-engaged with the inner casing 131a. The outer cylinder 151b and the inner cylinder 151a are united together by screw thread engagement. Reference numeral 152 denotes an O-ring for sealing.

Further, a sealing O-ring (cap sealing O-ring) 153 is disposed in the area of fit between the outer peripheral surface of the battery chamber-side end portion of the outer casing 131b and the inner peripheral surface of the outer cylinder 151b of the cap 150, thereby preventing water from entering the inside of the cap 150 through the area of fit therebetween.

A cap body 154, which is made of a metal of good electrical conductivity, is integrally connected to the other end portion of the inner cylinder 151a of the cap 150 at the inner side of the outer cylinder 151b by thread engagement and bonding. A first compression coil spring 155 is retained at one end thereof by the cap body 154 to bias the battery 100 toward the lamp chamber portion 130a through a retaining ring 156 which is axially movably fitted in the inner cylinder 151a, thereby ensuring the contact between the positive electrode of the battery 100 and the electrode plate 143a.

It should be noted that the first compression coil spring 155 is disposed in coaxial relation to the battery 100, and the retaining ring 156 abuts on the peripheral edge of the battery 100 so as not to contact the negative electrode of the battery 100. Reference numeral 157 denotes a ring-shaped washer with good slipping properties.

A movable contact member 158 contacts the negative electrode of the battery 100. The movable contact member 158 is formed in the shape of a cylinder, one end of which is closed, from a rigid metallic material of good electrical conductivity. The movable contact member 158 is fitted in the cap body 154 so as to be able to axially project from and withdraw into the cap body 154.

The movable contact member 158 has a contact 158a which is formed on the central portion of the bottom of the movable contact member 158. The movable contact member 158 is biased by a second compression coil spring 166 to press the contact 158a against the central portion of the negative electrode of the battery 100.

A guide pin 159 projects from the outer peripheral surface of the movable contact member 158. The guide pin 159 is engaged with an axial guide groove 160 which is formed in the cap body 154, thereby preventing the movable contact member 158 from rotating about the axis. A leaf spring 161 is secured at the proximal end thereof to the cap body 154 to press on the top of the guide pin 159 from the outer side.

Both the guide pin 159 and the leaf spring 161 are formed of a metal of good electrical conductivity. Thus, the negative electrode of the battery 100 is electrically connected to the negative-electrode plate 143b through metallic members of good electrical conductivity which are sealed in the illuminating light supply unit 130 so as to be isolated from the outside, and which are in contact with each other, such as the movable contact member 158, the guide pin 159, the leaf spring 161, the inner cylinder 151a, and the inner casing 131a.

Accordingly, the light source lamp 132 is lit by power supplied from the battery 100 with substantially no drop in voltage in the conducting path. Further, even when the illuminating light supply unit 130 is dipped in a medical fluid, no electrically conducting member will contact the medical fluid. Therefore, no corrosion occurs, and the electrically conducting members are capable of maintaining good electrical conductivity.

A rotating shaft 163 is fitted in the cylindrical movable contact member 158 so as to be rotatable about the axis of the cap 150. A switch control ring 164 is integrally connected by thread engagement and bonds to the head portion of the rotating shaft 163, which projects to the projecting end side of the cap 150.

The switch control ring 164 has a substantially bowl-like configuration, and is disposed so as to surround the end portion of the cap 150. A drainage hole 164a is provided in the outer edge of the switch control ring 164 to discharge water which may enter the space between the switch control ring 164 and the outer cylinder 151b during washing or disinfection.

Although a single drainage hole 164a will suffice in general, a plurality of drainage holes provide good draining performance. Therefore, it is preferable to provide two drainage holes at respective positions which are 180 degrees symmetrical with respect to each other. The drainage performance is further improved by providing three or more drainage holes.

Thus, since the drainage hole 164a is provided in the outer edge portion of the switch control ring 164, water entering the space between the switch control ring 164 and the outer cylinder 151b during washing or disinfection can be smoothly discharged, and no water collects in the space at the back of the switch control ring 164. Reference numeral 165 denotes a decorative plate.

The top portion of the movable contact member 158 is rotatably fitted to the inner peripheral surface of the end portion of the outer cylinder 151b. A sealing O-ring (switch sealing O-ring) 167 is disposed in the area of fit between the top portion of the movable contact member 158 and the inner peripheral surface of the outer cylinder 151b, thereby preventing water from entering the inside of the illuminating light supply unit 130. Thus, the illuminating light supply unit 130 is formed into a watertight structure which prevents water from externally entering the inside of the illuminating light supply unit 130 through any portion thereof.

It should be noted that there is no large difference in cross-sectional diameter between the switch sealing O-ring 167 and the cap sealing O-ring 153, but the ring diameter of the cap sealing O-ring 153 is much larger than that of the switch sealing O-ring 167. Accordingly, the sliding resistance to the rotating motion at the area of fit is higher at the cap sealing O-ring 153 than at the switch sealing O-ring 167.

In this embodiment, the ring diameter of the cap sealing O-ring 153 is about 3 times the ring diameter of the switch sealing O-ring 167. However, a noticeable difference can be produced in the sliding resistance to the rotating motion by providing at least a 2-fold difference in ring diameter.

As shown in FIG. 12, which is a sectional view taken along the line XII--XII in FIG. 11, lead pins 169 project outwardly from the outer peripheral surface of the rotating shaft 163 at right angles to the axis of the rotating shaft 163. leaf springs 170 give resistance to the lead pins 169 when these pins 169 reach extremity positions by rotating about the axis of the rotating shaft 163.

The side walls of the movable contact member 158 and the cap body 154, which are pierced with the lead pins 169, are provided with cam grooves 171 and circumferential relief grooves 172. Accordingly, as the lead pins 169 are rotated about the axis of the rotating shaft 163, the movable contact member 158 is forcedly moved axially by the action of the cam grooves 171 against the biasing force of the second compression coil spring 166, causing the contact 158a to separate from the negative electrode of the battery 100. Thus, the light source lamp 132 turns OFF.

FIG. 13 shows the cap portion of the illuminating light supply unit 130 in a state where the switch is turned OFF by rotating the switch control ring 164 as described above. FIG. 14 is a sectional view taken along the line XIV--XIV in FIG. 13.

In this embodiment, by rotating the switch control ring 164 through 90 degrees from the switch-ON position, the lead pins 169 rotate through the rotating shaft 163, which rotates together with the switch control ring 164 as one unit, causing the movable contact member 158 to move axially by the action of the cam grooves 171. Consequently, the contact 158a is separated from the negative electrode of the battery 100.

The axis of rotation of the switch control ring 164 is coincident with the axis of rotation of the inner cylinder 151a of the cap 150, which is in thread engagement with the inner casing 131a of the battery chamber portion 130b. However, the cap sealing O-ring 153 is greater than the switch sealing O-ring 167 in terms of the ring diameter and hence the sliding resistance, as described above.

Accordingly, when the switch control ring 164 is rotated, the outer cylinder 151b of the cap 150 does not rotate relative to the outer casing 131b of the battery chamber portion 130b, and there is no likelihood that the thread engagement between the inner cylinder 151a of the cap 150 and the inner casing 131a of the battery chamber portion 130b will loosen.

Further, the battery 100 is biased by the first compression coil spring 155 in a direction opposite to the direction in which the movable contact member 158 is separated from the battery 100 by the switching operation. In addition, the first compression coil spring 155, the battery 100, the contact 158a and the second compression coil spring 166 are disposed in coaxial relation to each other. Therefore, the battery 100 is stably held in the battery chamber portion 130b without rattling whether the switch is ON or OFF.

When the cap 150 is to be detached from the illuminating light supply unit 130 to replace the battery 100, it is only necessary for the user to disengage the inner cylinder 151a from the inner casing 131a by rotating the outer cylinder 151b directly with his or her fingers.

It should be noted that, as shown in FIG. 13, the leaf spring 161 for pressing the head portion of the guide pin 159 is bent so that the leaf spring 161 comes out of the state of pressing the guide pin 159 at the very moment the switch-OFF position is reached. Accordingly, a click action takes place at that position, thereby enabling a stable stationary condition to be obtained.

According to the third embodiment, a member which is made of a material of good electrical conductivity is provided in contact with the inner peripheral surface of a member of high corrosion resistance which armors the illuminating light supply unit, and the electrically conductive member is used as a conducting path for lighting the light source lamp. Therefore, the voltage drop in the conducting path is extremely small, and the light source lamp can be brightly lit.

If all the members that form a conducting path for supplying power to the light source lamp are disposed in the outer member that armors the illuminating light supply unit in a watertight manner, even when disinfection is carried out with a medical fluid, none of the members constituting the conducting path contact the medical fluid. Accordingly, the connecting portions of the conducting path are not corroded, and no lighting failure occurs.

Further, according to the third embodiment, an annular sealing member is fitted on the distal end portion of the illuminating light supply unit, which is detachably inserted into a cylindrical unit receiving socket which is provided on the control part, and an external thread for engagement with the unit receiving socket is formed on the distal end portion of the illuminating light supply unit at a position which is forward of the sealing member. Therefore, when the illuminating light supply unit is attached to or detached from the control part, the sealing member does not contact the internal thread of the unit receiving socket. Accordingly, the sealing member is not damaged when the illuminating light supply unit is attached to or detached from the control part. Thus, it is possible to prevent leakage of water during washing or disinfection.

FIGS. 15 and 16 show fourth and fifth embodiments, respectively, of the present invention, which are based on the third embodiment. In the fourth embodiment, a plurality of cap sealing O-rings 153 are provided, as shown in FIG. 15. In the fifth embodiment, the amount of compression of the cap sealing O-ring 153 is made larger than that of the switch sealing O-ring 167, thereby increasing the sliding resistance of the cap sealing O-ring 153. It should be noted that, in FIGS. 15 to 17, each O-ring is shown in the actual state of being compressed.

In a sixth embodiment of the present invention, as shown in FIG. 17, the switch sealing O-ring 167 is replaced by an X-ring 167a which has an X-shaped cross-sectional configuration, and which offers a relatively small sliding resistance. In this case, the ring diameter of the X-ring 167a may be enlarged, and it is also possible to reduce the cross-sectional area of the X-ring 167a.

In this embodiment, the X-ring 167a is disposed in the area of fit between the outer peripheral surface of the outer cylinder 151b and the inner peripheral surface of the switch control ring 164. Accordingly, no drainage hole 164a is needed. It should be noted that the X-ring 167a may be replaced by a ring-shaped sealing member having a V-shaped or other cross-sectional configuration.

To produce a difference in sliding resistance, it is also possible to use sealing members of materials which are different from each other in hardness, elasticity, coefficient of friction, etc., or to vary sealing members in cross-sectional diameter (cross-sectional area). It is also possible to coat a sealing member with an appropriate lubricant so that the required difference in sliding resistance is produced.

Thus, according to the third to sixth embodiments, the sliding resistance offered by the cap sealing member to the rotation of the cap is greater than the sliding resistance offered by the switch scaling member to the rotation of the switch. Therefore, when the switch is rotated for ON/OFF control, the cap, which is rotatable in coaxial relation to the switch, does not rotate together with the switch to become loose. Accordingly, the switching operation can be reliably performed.

While the invention has been described by reference to specific embodiments chosen for purposes of illustration, it should be apparent that numerous modifications could be made thereto by those skilled in the art without departing from the basic concept and scope of the invention. 

We claim:
 1. A portable endoscope system having an illuminating light guide for transmitting light for illuminating an object, said illuminating light guide having an entrance end portion disposed in an endoscope control part, and an illuminating light supply unit for supplying illuminating light to said illuminating light guide, said illuminating light supply unit comprising:a light source lamp for emitting illuminating light to said illuminating light guide; a battery for supplying lighting energy to said light source lamp; a cap detachable from said illuminating light supply unit by rotation, to enable loading and unloading of said battery into and out of said illuminating light supply unit; a switch attached to said cap and coaxially rotatable with respect to an axis of rotation of said cap to turn said light source lamp ON and OFF; a ring-shaped cap sealing member, provided on a rotating part of said cap, to prevent water from entering said illuminating light supply unit through said rotating part of said cap; and a ring-shaped switch sealing member, provided on a rotating part of said switch, to prevent water from entering said illuminating light supply unit through said rotating part of said switch, a sliding resistance of said cap sealing member to rotation of said cap being greater than a sliding resistance of said switch sealing member to rotation of said switch, said cap sealing member being positioned such that said sliding resistance of said cap sealing member remaining substantially constant upon rotation of said cap.
 2. A portable endoscope system according to claim 1, wherein said cap sealing member has a ring diameter larger than a ring diameter of said switch sealing member.
 3. A portable endoscope system according to claim 2, wherein said ring diameter of said cap sealing member is at least twice as large as said ring diameter of said switch sealing member.
 4. A portable endoscope system according to claim 1, wherein a plurality of said cap sealing members are provided on said rotating part of said cap, a number of said cap sealing members being greater than that of said switch sealing member.
 5. A portable endoscope system according to claim 1, wherein an amount of compression of said cap sealing member is larger than an amount of compression of said switch sealing member.
 6. A portable endoscope system according to claim 1, wherein said switch sealing member is a ring-shaped sealing member having a recessed cross-sectional configuration.
 7. A portable endoscope system according to claim 6, wherein said recessed cross-sectional configuration comprises an X-shape.
 8. A portable endoscope system according to claim 6, wherein said recessed cross-sectional configuration comprises a V-shape.
 9. The portable endoscope system according to claim 1, said switch sealing member being positioned such that said sliding resistance of said switch sealing member remaining substantially constant upon rotation of said switch.
 10. A portable endoscope system having an illuminating light guide for transmitting light for illuminating an object, said illuminating light guide having an entrance end portion disposed in an endoscope control part, and an illuminating light supply unit for supplying illuminating light to said illuminating light guide, said portable endoscope system comprising:a connecting mechanism that enables detachable connection of said illuminating light supply unit and said control part; a sealing device that seals a joint between said illuminating light supply unit and said control part, made by said connecting mechanism, in a watertight manner so that water will not enter into said portable endoscope system when said illuminating light supply unit is attached to said control part; and a sealing device that seals said control part in a watertight manner as a single unit; said illuminating light supply unit comprising:a light source lamp for emitting illuminating light to said illuminating light guide; a battery for supplying lighting energy to said light source lamp; a cap detachable from said illuminating light supply unit by rotation, to enable loading and unloading of said battery into and out of said illuminating light supply unit; a switch attached to said cap and coaxially rotatable with respect to an axis of rotation of said cap to turn said light source lamp ON and OFF; a ring-shaped cap sealing member, provided on a rotating part of said cap, to prevent water from entering said illuminating light supply unit through said rotating part of said cap; and a ring-shaped switch sealing member, provided on a rotating part of said switch, to prevent water from entering said illuminating light supply unit through said rotating part of said switch, a sliding resistance of said cap sealing member to rotation of said cap being greater than a sliding resistance of said switch sealing member to rotation of said switch, said cap sealing member being positioned such that sliding resistance of said cap sealing member remaining substantially constant upon rotation of said cap.
 11. The portable endoscope system according to claim 10, said switch sealing member being positioned such that said sliding resistance of said switch sealing member remaining substantially constant upon rotation of said switch. 